Push-button.



No. 683,692. Patented Out. I, l90l C. J. LANDIN.

PUSH BUTTON.

gApplicatiun filed. Feb. 9, 1901.)

(No Model.)

FIG-|- FIG E.

Attorney m: "cums PETER; w, PHQTO-LITHQ, WASHINGTON. u. z:v

UNrrs TATES CARL J. LANDIN, OF BOSTON, MASSACHUSETTS.

PUSH-BUTTON.

SPECIFICATION forming part of Letters Patent No. 683,692, dated October 1, 1901. Application filed February 9, 1901. Serial No. 46,631. (No model.)

T0 all whom it may concern.-

Be it known that I, CARL J. LANDIN, a citizen of the United States, residing at Boston, in the county of Sufiolk and State of Massachusetts, have invented certain new and useful Improvements in Push-Buttons; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to push-buttons for electric contact devices for completing electric circuits such as used in connection with call-bells; and it consists in the novel construction and combination of the parts hereinafter fully described and claimed.

In the drawings, Figure 1 is a front view of the device. Fig. 2 is a side view of the same.

A is a supporting-plate which is inclosed, together with the operating mechanism, in any approved casing or chamber suitably insulated for the purpose of protection and for preventing the escape of electricity.

B and C are two binding-posts secured to the plate A and having the battery-wires b and 0 connected to them, respectively.

D is a contact-spring which is kept constantly in circuit with the binding-post B by any approved means, such as a connectingpiece I). This spring is normally held out of contact with the binding-post C.

E is a cam-wheel mounted on a pin 2, which projects from the plate A, and F is a toothed ratchet-wheel, which revolves with the camwheel E.

G is a push-plate which is slidable crosswise of the ratchet-wheel. The push-plate is provided with a finger-piece G foroperating it and stops for limiting its motion, and it slides in suitable guides. A screw 9 engages with the pin 6, and g is a slot in the pushplate, which slides over the screw g. The screw guides the plate, and the ends of the slot constitute the stops which limit its motion; but any other approved guide or stops can be used. A stern h projects from the opposite end of the push-plate from the fingerpiece and is slidable in a guide plate h, which projects fromthe plate A. A spring j is interposed between the guide-plate h and the end of the push-plate. This spring encircles the stem h and normally holds one end of the slot g against the screw g. hooked pawl 76 is pivoted to the push-plate G and is held in engagement with the teeth of the ratchet-wheel F by means of a spring is. Vhen the push-plate is moved against the pressure of the spring j, the ratchet-wheel and the camwheel are partially revolved, and the parts are proportioned so that the camwheel revolves for one-half the pitch of its teeth at each full stroke of the push-plate toward the guide-plate h.

The cam-wheel normally rests with two of its teeth bearing equally against the contactspring D. XVhen the finger-piece is pressed to make one stroke of the push-plate, the cam-Wheel is partially revolved, so that the top of one of its teeth forces the contactspring D against the binding-post C and remains in a position substantially at a right angle to the said spring. The push-plate moves back automatically when the pressure on the finger-piece is relieved; but the contact-spring D remains in contact with the binding-post C, so that the electric circuit being established remains complete after the finger is removed from the fingerpiece. When the finger-piece is pressed a second time to make a second stroke of the pushplate, the cant-wheel is again partially revolved, so that its tooth ceases to hold the contact-spring against the binding-post, and the parts assume a similar position to that shown in the drawings.

The cam-Wheel is revolved step by step, and the contact is established at each alternate stroke of the push-plate. One stroke makes the circuit and the next following stroke breaks the circuit.

This push-button is very convenient in those places where it is desirable to complete an electric circuit and to maintain it with out holding the finger constantly upon the finger-piece by which the device is operated.

Whatl claim is-- 1. In a push-button, the combination, with a supporting-plate, of a contact-piece and a contact-spring insulated from each other, a revoluble toothed cam-wheel for pressing the said contact-spring against the contact-piece and holding it there, and means for revolving the cam wheel step by step for one-half the pitch of its teeth at each step, substantially as set forth.

2. In a push-button, the combination, with a supporting-plate, of a contact-piece and a contact-spring insulated from each other, a, revoluble toothed cam-Wheel for pressing the said contact-spring against the contact-piece and holding it there, a toothed ratchet-Wheel revolving with the cam-Wheel, a spring-controlled push-plate slidalole transversely of the ratchet-wheel, stops for limiting the motion of the push-plate, and a pawl carried by the push-plate and engaging with the ratchetwheel, whereby the cam-wheel is revolved step by step, substantially as set forth.

- In testimony whereof I affix my signature in presence of two witnesses.

CARL J. LANDIN.

\Vitnesses:

ALICE .LLJHURRAY, FREDERICK K. DAGGETT. 

